After a scan report or a doctor’s visit, many women go home asking: why me? In India it is often typed as “pcod kyu hota hai in hindi”. Relatives may blame junk food, stress or late marriage. The honest answer is kinder, and more useful.
PCOD and PCOS are two names for the same hormonal condition, now also called polyendocrine metabolic ovarian syndrome (PMOS). For what it is, its symptoms and diagnosis, see our PCOS hub on symptoms, tests and treatment.
PCOD causes: what doctors know, and what is still unknown
No single cause has been found. National Health Service (NHS) says the cause is unknown, but it may be to do with hormones such as insulin and testosterone not working properly. The US Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) says genetic and environmental factors both contribute.
Researchers describe a few linked problems that feed each other:
- Inherited genes make some women more prone to it.
- Insulin resistance: the body needs more insulin than usual to keep blood sugar normal, so insulin runs high.
- Raised androgens: the ovaries make more testosterone-like hormones than usual.
- A faster brain-to-ovary signal: the brain releases more luteinising hormone (LH), which pushes the ovaries to make more androgens.
Weight, especially around the waist, amplifies all of these. Because each problem worsens the others, PCOD is long-term and varies between women.
Genes and family history: the strongest known risk factor
PCOD runs in families. MedlinePlus, from the US National Library of Medicine, estimates that 20 to 40 percent of women with PCOS have an affected mother or sister. An Endocrine Society scientific statement describes a family study in which 22% of the sisters of women with PCOS met the criteria themselves, and a large Dutch twin study in which 72% of the variation in PCOS was due to genetic influences.
There is no single “PCOD gene”. NICHD says research points to 19 possible gene variants that raise risk. MedlinePlus explains that these variations are common: many women carry some without ever developing PCOS. It is the combination, with health and lifestyle factors, that matters.
A family history raises your risk; it does not decide your future. If your mother or sister has PCOD and you have irregular periods, acne or excess hair, tell your doctor.
Insulin resistance and high insulin
Insulin moves sugar from your blood into your cells. In insulin resistance the cells respond poorly, so the pancreas makes extra insulin to keep blood sugar normal. The 2023 international PCOS guideline calls insulin resistance a key feature and part of how PCOS develops.
High insulin does more than affect sugar. The Endocrine Society statement explains that insulin adds to the ovaries’ androgen production and lowers sex hormone-binding globulin (SHBG), a liver protein that holds testosterone in check, so more testosterone is free to act. NICHD calls it a cycle that is hard to break. High insulin is also linked to dark, velvety skin in the neck folds or armpits (acanthosis nigricans).
Insulin resistance is not only a weight problem. A small Australian study using the most accurate research test found insulin resistance in 75% of lean women with PCOS and 95% of women with PCOS at a higher weight, against 62% of women at a higher weight without PCOS. The women were mostly white, but the study supports the idea that PCOS carries its own insulin resistance, which extra weight adds to.
Do not rush to a “fasting insulin” test. The guideline says clinic insulin tests are of limited clinical relevance and should not be used in routine care. The hub’s diagnosis and tests section explains the glucose tests worth discussing.
Raised androgens and the brain–ovary hormone signal
Androgens, such as testosterone, are hormones every woman makes in small amounts. In PCOD the ovaries make more than usual. NICHD explains that high androgens can interfere with the brain’s signals that control ovulation, so an egg is released only sometimes or not at all. They can also make small egg sacs (follicles) stop growing and pile up, which is what looks like “cysts” on a scan.
The brain normally releases LH and follicle-stimulating hormone (FSH) in a steady rhythm. The Endocrine Society statement describes PCOS as having a persistently fast pulse of the brain’s signalling hormone, high LH and low or low-normal FSH.
So the loop runs: high LH and high insulin push up androgens; androgens disturb the brain’s signal and stop follicles maturing; without ovulation, periods become irregular.
Weight and belly fat: an amplifier, not the root cause
Extra weight can bring PCOD out in women already prone to it, and make it worse. Studies that use genes to test cause and effect (Mendelian randomization) suggest a higher body mass index (BMI) is a cause of PCOS, while PCOS itself does not raise BMI. A 2022 review concluded that the balance of evidence strongly supports this, though most of the studies were in women of European ancestry.
But weight is not the whole story:
- The Endocrine Society statement says it is still debated whether obesity alone can cause PCOS; obesity can worsen existing features.
- A review of Indian research in the Indian Journal of Medical Research (IJMR) notes that PCOS occurs equally in women with and without obesity, and names fat around the abdomen as the major factor for insulin resistance in PCOS.
- The international guideline found no consistent evidence that women with PCOS eat differently or move less than other women, and says many have underlying mechanisms that drive greater weight gain over time.
Slim women get PCOD too, and gaining weight with PCOD is not laziness. Waist size tells more than the scale; our BMI calculator with Indian cut-offs is a starting point, and the hub explains Indian waist thresholds. If you are at a higher weight, see why PCOS weight loss feels harder and what helps. Weight loss can ease symptoms but cannot change the genes behind PCOD, so lean women and women who lose weight still need regular checks.
Before birth: a theory still being tested
Some researchers think PCOD may begin in the womb. NICHD says animal studies suggest that exposure to higher androgen levels before birth may raise the chance of PCOS. The Endocrine Society statement says the human evidence is less convincing and the role of fetal origins remains uncertain; in one twin study, women who had shared the womb with a twin brother were no more likely to have PCOS.
Nothing a mother ate or did in pregnancy has been shown to cause PCOD in her daughter.
Why Indian women may be at higher risk
South Asian women appear to be affected more often, and sometimes more severely:
- NHS says PCOS is more likely if you are from an Asian background.
- The international guideline says prevalence may be higher in South East Asian and Eastern Mediterranean regions. In the World Health Organization’s grouping of countries, India sits in the South-East Asia region.
- A small UK study compared 47 South Asian and 40 white women with PCOS of similar BMI and waist-to-hip ratio. The South Asian women sought treatment younger, had more excess hair, acne and dark skin patches, and had higher fasting insulin and lower insulin sensitivity.
- The hub lists a family history of type 2 diabetes as a risk factor, and the UK study notes that type 2 diabetes is commoner in South Asians.
If diabetes runs in your family, take irregular periods, excess hair or dark skin patches seriously, whatever your weight.
Is junk food or stress the PCOD reason? Myths versus evidence
Most popular explanations blame the woman. Few hold up.
| What people say | What the evidence says | Verdict |
|---|---|---|
| “Junk food and outside food cause PCOD.” | We found no evidence that any single food causes PCOD. Eating that leads to weight gain can bring it out in women already prone to it. The Endocrine Society statement says the best diet for PCOS lacks definitive proof. | Partly: weight gain can contribute; no single food causes it |
| “Cold drinks and sugar cause PCOD.” | We found no study showing sugary drinks cause PCOD directly. They can add to weight gain, which can worsen insulin resistance. | Not proven; worth cutting down anyway |
| “Stress causes PCOD.” | We found no study showing this. Women with PCOS report more stress, but a 2023 Austrian study found their saliva stress hormones were no different once age and weight were accounted for. NHS lists stress as a separate cause of late periods. | Not proven; stress can delay periods |
| “Late marriage or not having a baby causes PCOD.” | We found no evidence. Symptoms usually start around puberty, NHS says, long before marriage. Marriage and pregnancy do not treat it either. | Myth |
| “Birth-control pills cause PCOD.” | We found no evidence. The guideline names the combined pill as first-line treatment for irregular periods and excess hair in PCOS. It lowers androgens, so it can hide PCOS signs that show again after stopping. | Myth |
| “Tight jeans or clothes cause PCOD.” | We found no study linking clothing to PCOD, a hormonal condition. | Myth |
| “Mobile phones, laptops or Wi-Fi cause PCOD.” | We found no study showing this. | Myth |
| “Plastic bottles and tiffins cause PCOD.” | Some studies find more of the plastic chemical bisphenol A (BPA) in women with PCOS, but the Endocrine Society statement says these limited data have not established cause and effect. | Unproven; being studied |
| “You got PCOD because you are overweight or lazy.” | PCOD occurs at every body size and is strongly inherited. The guideline asks doctors to avoid weight stigma. | Myth, and an unkind one |
You did not cause your PCOD. Habits change how strongly it shows, so they still matter, but a tendency you were largely born with is not a personal failure.
Why knowing the cause shapes what helps
Because PCOD has several drivers, treatment aims at the ones that matter most for you:
- Insulin resistance: regular activity, steady meals and, if your doctor decides, insulin-sensitising medicine. A glucose tolerance test is useful whatever your weight.
- Raised androgens and irregular periods: hormonal treatments that regulate periods and protect the womb lining, or reduce acne and hair growth.
- Higher weight: modest weight loss, if you are above a healthy weight, can improve periods and insulin resistance.
- Family history: tell sisters and daughters, so their symptoms are checked early.
Healthy habits help with insulin and weight, but they cannot remove a genetic tendency, guarantee regular periods or replace medical treatment. For the options, read our guide to PCOD treatment and medicines.
When to see a doctor
The hub has the full list of PCOS warning signs.
Emergency: get help now (call 112)
- Bleeding that soaks through a pad soon after you put it on, or heavy bleeding with dizziness or fainting.
- If you could be pregnant: severe or one-sided lower tummy pain, pain in the tip of your shoulder, or fainting.
- Thoughts of harming yourself. Contact emergency services or Tele Mental Health Assistance and Networking Across States (Tele-MANAS), the Government of India’s mental-health helpline.
Prompt review: within days to a few weeks
- Excess hair, acne or scalp hair loss that worsens quickly over a few months, or a deepening voice. The guideline says rapid change needs checking for rarer causes, such as a hormone-producing tumour.
- No period for three months or more when you are not pregnant.
- A missed period when you could be pregnant: take a test and see a doctor if it is positive or you are unsure.
Routine review
Book an appointment for irregular periods, unwanted hair, persistent acne, scalp thinning, dark skin patches or unexplained weight change, especially if a mother or sister has PCOD or diabetes runs in your family. If you are planning a pregnancy, see your doctor first.
How Disha can help
Disha is an AI health coach that chats and calls in Hindi, English and Hinglish. It does not replace a doctor, and it does not diagnose, prescribe or provide emergency care. It helps with the daily habits your doctor recommends: meals, movement, sleep and stress. Its onboarding call of about 15–20 minutes is conducted by Disha, the AI; no human doctor is on the call. Read how Disha coaching works.
This is not medical advice. This page is general education for adults (18+), not a diagnosis or treatment plan. Do not start, stop or change any medicine, including the contraceptive pill, because of it. If you are pregnant, breastfeeding or have a current or past eating disorder, get individual advice before changing how you eat or exercise. In an emergency, call 112.
Frequently asked questions
What are the main causes of PCOD?
The exact cause is unknown. The main known drivers are inherited genes, insulin resistance with high insulin, raised androgens from the ovaries, and a faster hormone signal from the brain that raises LH. Extra weight, especially around the waist, can bring PCOD out or worsen it. These factors feed each other, which is why PCOD is long-term and varies between women.
Is the PCOD problem caused by something I did?
No. PCOD is strongly inherited: a Dutch twin study estimated that 72% of the variation in PCOS is due to genes. Habits such as food, activity and sleep can change how strongly it shows, but they are not the root cause. The international guideline found no consistent evidence that women with PCOS eat or move differently from other women.
Is PCOD genetic? Will my daughter get it?
PCOD runs in families, but there is no single gene and it is not certain to pass on. MedlinePlus estimates that 20 to 40 percent of women with PCOS have an affected mother or sister. If you have PCOD, your daughter has a higher chance than average. Let her know, so that irregular periods, acne or excess hair after puberty are checked rather than ignored.
Can thin women get PCOD?
Yes. An Indian review notes that PCOS occurs equally in women with and without obesity. Lean women with PCOS can still have insulin resistance: one small study found it in 75% of lean women with PCOS. That is why doctors suggest a glucose tolerance test for everyone with PCOS, whatever their weight, and why slim women should not be told their symptoms cannot be PCOD.
Do birth-control pills cause PCOD?
We found no evidence that they do. The combined pill is a first-line treatment for irregular periods and excess hair in PCOS, according to the international guideline. Because the pill lowers androgens and gives regular bleeds, it can hide PCOS while you take it, so signs may appear after stopping. That is unmasking, not a cause. Never stop a prescribed pill without advice.
Can stress cause PCOD?
We found no study showing that stress causes PCOD. Women with PCOS often report more stress, which may come from living with its symptoms. Stress can delay a period, and NHS lists it as a separate cause of missed periods. If your periods stay irregular for months, see a doctor rather than assuming it is stress, because PCOD, thyroid problems or other causes may need checking.
If I fix the cause, will PCOD go away?
Not completely. Genes are part of the cause and cannot be changed, there is currently no cure, and the international guideline suggests the diagnosis can be considered lifelong. Symptoms can improve a lot with treatment and habits, especially when insulin resistance or extra weight are addressed. Our guide on whether PCOD can be cured explains what “reversal” claims really mean.
Sources
- Teede HJ, Tay CT, Laven JJE, Dokras A, Moran LJ, Piltonen TT, Costello MF, Boivin J, Redman LM, Boyle JA, Norman RJ, Mousa A, Joham AE. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. Journal of Clinical Endocrinology and Metabolism, 2023. Supports: insulin resistance as a key and pathophysiological feature; clinic insulin tests not for routine care; prevalence possibly higher in South East Asian and Eastern Mediterranean regions; no consistent evidence of lifestyle differences related to weight, and underlying mechanisms driving weight gain; weight stigma; combined pill as first-line treatment and its effect on androgen testing; rapid symptom change and androgen-secreting tumours; diagnosis considered lifelong.
- NHS. Polyendocrine metabolic ovarian syndrome (PMOS) and Missed or late periods. Current patient guidance. Supports: cause unknown, possibly insulin and testosterone not working properly; higher likelihood with a close relative affected or an Asian background; symptoms usually starting at puberty; stress as a cause of missed periods.
- Eunice Kennedy Shriver National Institute of Child Health and Human Development. What causes PCOS? Current patient information. Supports: genetic and environmental factors; 19 possible gene variants; animal research on androgen exposure in the womb; androgens disturbing the brain’s ovulation signals and follicle growth; the insulin–androgen cycle; high insulin and acanthosis nigricans.
- MedlinePlus Genetics (US National Library of Medicine). Polycystic ovary syndrome. Current consumer genetics information. Supports: a combination of genetic, health and lifestyle factors; common gene variations present in women with and without PCOS; 20 to 40 percent with an affected mother or sister.
- Dumesic DA, Oberfield SE, Stener-Victorin E, Marshall JC, Laven JS, Legro RS. Scientific Statement on the Diagnostic Criteria, Epidemiology, Pathophysiology, and Molecular Genetics of Polycystic Ovary Syndrome. Endocrine Reviews (Endocrine Society), 2015. Supports: rapid brain hormone pulses, high LH and low or low-normal FSH; insulin adding to ovarian androgen production and lowering SHBG; 22% of sisters affected in a family study; the Dutch twin estimate of 72% genetic influence; debate on obesity as a cause and its worsening effect; weaker human evidence for fetal origins, and no difference in PCOS for women from opposite-sex twin pairs; BPA data not establishing cause; best diet lacking definitive proof.
- Zhu T, Goodarzi MO. Causes and Consequences of Polycystic Ovary Syndrome: Insights From Mendelian Randomization. Journal of Clinical Endocrinology and Metabolism, 2022. Supports: genetic studies suggesting higher BMI and fasting insulin play a causal role in PCOS; PCOS not raising BMI; balance of evidence strongly supporting BMI as causal; mainly European-ancestry data.
- Stepto NK, Cassar S, Joham AE, Hutchison SK, Harrison CL, Goldstein RF, Teede HJ. Women with polycystic ovary syndrome have intrinsic insulin resistance on euglycaemic-hyperinsulaemic clamp. Human Reproduction, 2013. Supports: insulin resistance in 75% of lean women with PCOS, 95% of overweight women with PCOS and 62% of overweight controls; a largely white study population.
- Wijeyaratne CN, Balen AH, Barth JH, Belchetz PE. Clinical manifestations and insulin resistance (IR) in polycystic ovary syndrome (PCOS) among South Asians and Caucasians: is there a difference? Clinical Endocrinology, 2002. Observational UK study. Supports: 47 South Asian and 40 white women with similar BMI and waist-to-hip ratio; younger presentation, more hirsutism, acne and acanthosis nigricans, higher fasting insulin and lower insulin sensitivity in South Asian women; type 2 diabetes commoner in South Asians.
- Ganie MA, Vasudevan V, Wani IA, Baba MS, Arif T, Rashid A. Epidemiology, pathogenesis, genetics & management of polycystic ovary syndrome in India. Indian Journal of Medical Research, 2019. Supports: PCOS occurring equally in women with and without obesity in Indian studies, with insulin-resistance markers more common in obesity; abdominal fat as the major factor for insulin resistance.
- Medical University of Vienna researchers. A case-control study about markers of stress in normal-/overweight women with polycystic ovary syndrome and in controls. Frontiers in Endocrinology, 2023. Case-control study of 31 women with PCOS and 31 controls. Supports: no difference in salivary stress markers after correcting for age and BMI; higher self-reported stress in women with PCOS.
Related reads
- PCOS in India: symptoms, tests, treatment and daily care: the overview this page sits under. It covers what PCOS is, diagnosis and treatment in full.
- PCOD and PCOS symptoms in women: the signs these hormone changes produce, from irregular periods to acne and hair growth.
- PCOD treatment and medicines: how each cause is treated, including medicines, their uses and their limits.
- Why weight loss feels harder with PCOS, and what actually helps: for readers at a higher weight who want to lose some safely.
- All PCOS articles: every Disha guide on PCOS in one place.
- BMI calculator with Indian cut-offs: a screening number for weight-related risk, not a test for PCOD.
